Distal access aspiration guide catheter

ABSTRACT

Distal access aspiration guide catheter system and methods for delivering implantable devices, catheters, or substances in or near and/or restoring flow through body lumens, such as blood vessel lumens are described. A distal access aspiration guide catheter having a proximal, medial, and distal possessing high flexibility, high resistance to kinking and a large lumen to wall thickness ratio.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 13/537,246, filed Jun. 29, 2012, which claims the benefit ofU.S. Provisional Application Ser. No. 61/503,546, filed on Jun. 30,2011, the entire contents of each of which are herein incorporated byreference.

BACKGROUND 1. Technical Field

The present disclosure relates generally to medical devices and methodsand more particularly to catheter-based systems and methods useable foraccessing, diagnosing, or treating defects in blood vessels, such asblood vessels of the brain.

2. Background of the Related Art

Stroke is a common cause of death and disability. In the United States,approximately 700,000 patients suffer from stroke annually. Stroke is asyndrome characterized by the acute onset of a neurological deficit thatpersists for at least 24 hours, reflecting focal involvement of thecentral nervous system, and is the result of a disturbance of thecerebral circulation. Its incidence increases with age. Risk factors forstroke include systolic or diastolic hypertension, hypercholesterolemia,cigarette smoking, heavy alcohol consumption, and oral contraceptiveuse.

Hemorrhagic stroke accounts for 20% of the annual stroke population.Hemorrhagic stroke often occurs due to rupture of an aneurysm orarteriovenous malformation (AVM), causing bleeding into the brain tissueand resultant infarction of brain tissue. The remaining 80% of strokesare due to ischemia that occurs due to occlusion of a blood vessel thatdeprives brain tissue of oxygen-carrying blood. Ischemic strokes areoften caused by emboli or pieces of thrombotic tissue that havedislodged and traveled from other body sites, or from the cerebralvessels themselves, to occlude in the narrow cerebral arteries moredistally. When a patient presents with neurological symptoms and signs,which resolve completely within 1 hour, the term transient ischemicattack (TIA) is used. Etiologically, TIA, and ischemic stroke share thesame pathophysiologic mechanisms and thus represent a continuum based onpersistence of symptoms and extent of ischemic insult.

Emboli occasionally form around the valves of the heart or in the leftatrial appendage during periods of irregular heart rhythm and then aredislodged and follow the blood flow into the distal regions of the body.Those emboli can pass to the brain and cause an embolic stroke. As willbe discussed below, many such occlusions occur in the middle cerebralartery (MCA), although such is not the only site where emboli come torest.

When a patient presents with neurological deficit, a diagnostichypothesis for the cause of stroke can be generated based on thepatient's history, a review of stroke risk factors, and a neurologicexamination. If an ischemic event is suspected, a clinician cantentatively assess whether the patient has a cardiogenic source ofemboli, large artery extracranial or intracranial disease, small arteryintraparenchymal disease, or a hematologic or other systemic disorder. Ahead CT scan is often performed to determine whether the patient hassuffered an ischemic or hemorrhagic insult. Blood would be present onthe CT scan in subarachnoid hemorrhage, intraparenchymal hematoma, orintraventricular hemorrhage.

To reach these lesions or occlusions microcatheter and microguidewiremust be employed, but often the column support of these microcathetersis not strong enough to navigate through the distal reaches of theneurovasculature to effectively treat these sites. Often guide cathetersare employed to act as a conduit to help support microcatheter access.Traditional guide catheters designed for coronary or peripheral use(U.S. Pat. Nos. 5,180,376 & 5,484,425 Fischell, U.S. Pat. No. 5,045,072Castillo, U.S. Pat. No. 5,279,596 Castaneda, U.S. Pat. No. 5,454,795Samson and U.S. Pat. No. 5,733,400 Gold), typically are not positionedabove the skull base and limit their effectiveness in supportingmicrocatheters in the distal cerebrovasculature. Newer distal accessguide catheters have been developed which are slightly longer, thinner,a bit more flexible than the early generations, but are constructed withthe same manufacturing techniques as described in U.S. Pat. Nos.5,180,376 & 5,484,425 Fischell, U.S. Pat. No. 5,045,072 Castillo, U.S.Pat. No. 5,279,596 Castaneda, U.S. Pat. No. 5,454,795 Samson and U.S.Pat. No. 5,733,400 Gold, but have not solved the kinking problem (e.g.,Neuron Penumbra Recall—Oct. 2, 2009).

SUMMARY

This description may use the phrases “in an embodiment,” “inembodiments,” “in some embodiments,” or “in other embodiments,” whichmay each refer to one or more of the same or different embodiments inaccordance with the present disclosure. For the purposes of thisdescription, a phrase in the form “A/B” means A or B. For the purposesof the description, a phrase in the form “A and/or B” means “(A), (B),or (A and B)”. For the purposes of this description, a phrase in theform “at least one of A, B, or C” means “(A), (B), (C), (A and B), (Aand C), (B and C), or (A, B and C)”.

As used herein, the terms proximal and distal refer to a direction or aposition along a longitudinal axis of a catheter or medical instrument.The term “proximal” refers to the end of the catheter or medicalinstrument closer to the operator, while the term “distal” refers to theend of the catheter or medical instrument closer to the patient. Forexample, a first point is proximal to a second point if it is closer tothe operator end of the catheter or medical instrument than the secondpoint. The measurement term “French”, abbreviated Fr or F, is defined asthree times the diameter of a device as measured in mm. Thus, a 3 mmdiameter catheter is 9 French in diameter. The term “operator” refers toany medical professional (i.e., doctor, surgeon, nurse, or the like)performing a medical procedure involving the use of aspects of thepresent disclosure described herein.

In an aspect of the present disclosure, a catheter device for accessing,diagnosing, or treating defects in blood vessels, such as blood vesselsof the brain is provided. The catheter device includes a tubular memberhaving an inner lumen and an outer surface that includes a metallicstructure having spaces defined therein and a polymeric materialdisposed within the spaces. An inner liner extends through the lumen ofthe tubular member and defines an inner lumen of the catheter. There isan outer covering on the outer surface of the tubular member. Thepolymeric material disposed within the spaces is different from thematerials of the inner liner and outer cover.

In another aspect of the present disclosure, a guide catheter section isprovided that includes an elongate tubular catheter body having aproximal end and a distal end and a passageway defining an inner lumenextending between those ends. The elongate tubular catheter bodyincludes an inner tubular liner of a first liner material in coaxialrelationship with an outer tubular cover and a tubular member betweenthe inner liner and outer cover. The tubular member includes a metallicstructure and a polymeric kink resistance member, having the samehandedness. The catheter section, in the region of the distal end, has awall thickness to inner diameter ratio in excess of 16:1 and a lateralflexibility of greater than 1200°/in-lb, and ultimate tensile strengthof greater than 15N's

In yet another aspect of the present disclosure, a guide catheterincludes an elongate tubular member having a proximal end and a distalend and a passageway defining an inner lumen extending between thoseends. The elongate tubular member has a relatively stiff proximalsegment that includes an inner proximal tubular liner having a proximalliner material in coaxial relationship with an outer proximal tubularcover having a proximal cover material. The proximal segment alsoincludes a metallic braid structure braided upon said inner proximaltubular liner and covered by said outer proximal tubular cover. Theelongate tubular member also includes a relatively flexible distalsegment. The distal elongate tubular member includes an inner tubularliner of a first liner material in coaxial relationship with an outertubular cover having a first cover material. The distal elongate tubularmember also includes at least a metallic and a polymeric kink resistancemember structure having the same handedness and both wound exterior tothe inner tubular liner, and covered by said outer tubular cover. Thecatheter section, in the region of the distal end, having a wallthickness to inner diameter ratio in excess of 16:1 and a lateralflexibility of greater than 1200°/in-lb, and ultimate tensile strengthof greater than 15N's. The elongate tubular member also includes atleast one intermediate segment defining a passageway between therelatively stiff proximal segment and the relatively flexible distalsegment with has a transition from the braided stiffening structure tothe metallic and polymeric kink resistance member structure.

In any or all of the aspects described above, the metallic structure mayinclude a nickel titanium alloy such as a nickel titanium alloy ribbon.The metallic structure may be a metal helix having a helical gap wherethe helical gap is of continuous width or the dimension(s) of the metalhelix and/or width of the helical gap varies. Alternatively, themetallic structure may be a metal braid having a number of pics wherethe number of pics per inch varies.

The polymeric material may be a thermoset polymer, an elastomer, a castelastomer, or a cast polyurethane. The cast polyurethane may include athermoset polyurethane adhesive. The inner liner may include at leastone material selected from the group consisting of: fluoropolymers;PTFE; PFA and FEP. The outer cover may include at least one materialselected from the group consisting of: polyesters and polyolefins.

The catheter device may have a plurality of regions along its lengthwherein dimension(s) of the metal helix and/or the width of the helicalgap differ between said regions. Alternatively, the catheter device mayhave a plurality of regions along its length wherein dimension(s) thenumber of pics per inch differ between said regions. Such regions mayinclude a proximal region, a medial region and a distal region.

The outer cover on the proximal region may have a polyester having athickness of about 0.001 inch, the outer cover on the medial region mayhave polyester having a thickness of about 0.0005 inch, and the outerover on the distal region may have polyolefin having a thickness ofabout 0.0005 inch.

The distal region has a lateral flexibility of greater than 1200°/in-lband a kink radius of about 0.174 inch+/−0.008 inch or less.

In other aspects, the catheter device may also include a balloon wherethe balloon is a compliant balloon.

In a further aspect of the present disclosure, a method for treating ordiagnosing a disorder in a human or animal subject is provided thatincludes inserting into the subject's vasculature any of the catheterdevices described herein. After inserting the catheter device, asubstance or device is delivered through the lumen of the catheterdevice and the substance or device is used to treat or diagnose thedisorder.

The catheter may be advanced into a blood vessel located within thesubject's skull. The blood vessel into which the catheter device isadvanced is selected from the group consisting of: carotid artery,cerebral artery, anterior cerebral artery, middle cerebral artery andposterior cerebral artery.

In yet another aspect of the present disclosure, a method formanufacturing a catheter is provided. The method includes forming orobtaining a metallic structure having spaces defined therein and causingpolymeric material to be disposed within the spaces such that thepolymeric material and the metallic structure, in combination, form atubular member having an outer surface and a lumen. An inner liner isdisposed within the lumen of the tubular member and an outer cover isdisposed on the outer surface of the tubular member.

The inner liner may be disposed on a mandrel and the metallic structureis then positioned on top of the inner liner. The metallic structure mayinclude a nickel titanium alloy disposed about the inner liner and thenheat set. A flowable polymer mixture is cast into the spaces and allowedto solidify, thereby forming the tubular member with the inner linerdisposed therein. The polymer may be a polymer adhesive such as athermoset polymer.

A release agent or barrier is applied to one or more selected areas ofthe metallic structure to deter or interrupt adhesion of the polymeradhesive to the selected areas of the metal helix. The polymer adhesivecauses adhesion between the tubular member and the inner liner.

The method also includes causing a quantity of polymer adhesive to bedisposed between the outer surface of the tubular member and the innersurface of the outer cover to cause adhesion between the tubular memberand the outer cover.

The outer cover comprises a tube that initially has an inner diameterthat is larger than the outer diameter of the tubular member and whereinthe outer cover is advanced over the tubular member and contacts thetubular member to cause a snug fit on the outer surface of the tubularmember. The outer cover is heat shrunk onto the outer surface of thetubular member. A radiographic marker may be disposed on or in thecatheter device. In addition, a hydrophilic coating may be applied to anouter surface of the outer cover.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will become more apparent in light of the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1A illustrates a side view of one embodiment of a catheteraccording to an embodiment of the present disclosure;

FIG. 1B illustrates a cross-sectional view of the catheter taken alongthe line 1B-1B of FIG. 1;

FIG. 1C illustrates a cross-sectional view of the catheter taken alongthe line 1C-1C of FIG. 1;

FIG. 1D illustrates a detailed view of the area outlined in FIG. 1;

FIG. 2A illustrates a cross-sectional view of the catheter taken alongthe line 2A-2A of FIG. 1

FIG. 2B illustrates a detailed view of an area outlined in FIG. 2A;

FIG. 2C illustrates a detailed view of an area outlined in FIG. 2A;

FIG. 3A illustrates a side view of a liner and reinforcement layerassembly of the catheter illustrated in FIG. 1;

FIG. 3B illustrates a side view of the proximal, medial, and distalcoils according to an embodiment of the present disclosure;

FIG. 3C illustrates a side view of the proximal, medial, and distalbraids according to another embodiment of the present disclosure;

FIG. 4 illustrates a side view of a first adhesive layer arrangement ofthe catheter illustrated in FIG. 1;

FIG. 5 illustrates a side view of a second adhesive layer and coverarrangement of the catheter illustrated in FIG. 1;

FIG. 6 illustrates a side view of a coated catheter; and

FIG. 7 illustrates a side view of a catheter according to anotherembodiment of the present disclosure.

DETAILED DESCRIPTION

Particular embodiments of the present disclosure are describedhereinbelow with reference to the accompanying drawings; however, thedisclosed embodiments are merely examples of the disclosure and may beembodied in various forms. Well-known functions or constructions are notdescribed in detail to avoid obscuring the present disclosure inunnecessary detail. Therefore, specific structural and functionaldetails disclosed herein are not to be interpreted as limiting, butmerely as a basis for the claims and as a representative basis forteaching one skilled in the art to variously employ the presentdisclosure in virtually any appropriately detailed structure. Likereference numerals may refer to similar or identical elements throughoutthe description of the figures.

There is provided in accordance with one aspect of the presentdisclosure, a method for accessing regions of the vasculature throughtortuous anatomy. Such vasculature includes the cerebrovasculaturewherein access to the Circle of Willis and beyond is exceedinglydifficult due to the carotid siphon or vertebral artery anatomy thatmust be traversed to reach such locations without undo trauma or vesselstraightening. The method comprises the steps of providing a catheterhaving a proximal end and a distal end. The distal end of the catheteris inserted into the artery, and the support is distally advanced.Negative pressure can be applied to the proximal end of the catheter, oran affixed aspiration port, to draw the thromboembolic material into thedistal section. Catheters and other instrumentation (working devices)can be inserted through the distal access aspiration guide catheterwithin the vasculature to gain access to locations where flexibility,kink resistance, torqueability, and column strength are required.

Typical arteries may be, among other examples, the common carotidartery, the internal carotid artery, the carotid siphon, the Circle ofWillis, etc. Alternatively, the artery may be the middle cerebral arteryor the anterior cerebral artery, or elsewhere in the brain.

The method may additionally comprise the steps of introducing oxygenatedmedium into the artery through the aspiration lumen, or infusingpharmaceutical agent into the artery through the aspiration lumen. Thepharmaceutical agent may be a vasodilator such as nifedipine ornitroprusside. The pharmaceutical agent may alternatively comprise t-PA.The thromboembolic material may be located using intravascularultrasound, or carotid Doppler imaging techniques.

In accordance with another aspect of the present disclosure, there isprovided an intracranial aspiration catheter. In accordance with thepresent disclosure, there is provided a method of establishing a flowpath through a catheter, positioned across a non-linear segment ofvasculature.

In certain embodiments, the aspiration catheter can serve as a guidecatheter for placement of the micro-catheter. The guide catheter isadvanced to a target region in cooperation with a guidewire to allow forsteering and manipulation through the vasculature. In an exemplaryprocedure, the guidewire and guide catheter are introduced into thevasculature at a site within a femoral or iliac artery. Using aSeldinger technique, or other percutaneous procedure, a hollow 18-Gaugeneedle can be introduced into a femoral artery via percutaneousprocedure. A guidewire is next advanced through the hollow needle andinto the arterial tree. The hollow needle is next removed and anintroducer sheath is advanced into the arterial tree. The guide catheteris next advanced through the catheter introducer either through the sameguidewire or through a larger guidewire suitable for aortic traverse.The guide catheter is advanced through the aortic arch, into a carotidartery, through the carotid siphon and into a region proximate thecircle of Willis. The guide catheter, because of its flexibility andhigh kink resistance can easily inserted through tortuous anatomy beyondthe carotid siphon or the vertebral and basilar arteries. Once properlyplaced, the guide catheter can be utilized as a large conduit for theinsertion of other working devices. Because of its large inner diametermultiple devices can be inserted. The guide catheter can serve as anaspiration device and as a shield for retrieval of debris, thrombus, orother material from the vasculature.

The guide catheter is terminated, at its proximal end, with a luer orhemostasis valve and optionally with a connector offering multipleaccess ports, each of which can be valved or be terminated with astopcock, etc.

There is disclosed a distal access aspiration catheter 100 in accordancewith one aspect of the present disclosure. Although primarily describedin the context of distal access aspiration guide catheter with a singlecentral lumen, catheters of the present disclosure can readily bemodified to incorporate additional structures, such as permanent orremovable column strength enhancing mandrels, two or more lumens topermit drug or irrigant infusion or radiation delivery or to supplyinflation media to an inflatable balloon, or combinations of thesefeatures, as will be readily apparent to one of skill in the art in viewof the disclosure herein. Further, catheters of the present disclosuremay have a rapid exchange configuration. In addition, the presentdisclosure will be described primarily in the context of providingdistal vascular access for other endovascular working devices andremoving obstructive material from remote vasculature in the brain.

The catheters disclosed herein may readily be adapted for use throughoutthe body wherever it may be desirable to introduce a very flexible thinwalled catheter and kink resistant, which provides a relatively largediameter aspiration or supported working channel. For example, cathetershafts in accordance with the present disclosure may be dimensioned foruse throughout the coronary and peripheral vasculature, thegastrointestinal tract, the urethra, ureters, Fallopian tubes and otherlumens and potential lumens, as well. The lumen structure of the presentdisclosure may also be used as a minimally invasive percutaneous tissuetract expander, such as for diagnostic or therapeutic access to a solidtissue target (e.g., breast biopsy or tissue excision).

FIGS. 1A-1D illustrate a guide catheter 100 according to an embodimentof the present disclosure. In this example, the guide catheter 100comprises an elongate body having a proximal section 101, a medialsection 102 and a distal section 103. A lumen 104 extends through thecatheter 100. The elongate body of the catheter comprises an inner lineror sleeve 105, and a kink resistant member 106. A distal outer cover 108is disposed on the distal section 103 and medial section 102 and aproximal tubular cover 109 is disposed on the proximal section 101. Aluer or manifold 110 is provided on the proximal end of the elongatecatheter body. Optionally, one or more radiographic marker(s) 112 may bepositioned on or in the elongate catheter body, such as at the distaltip as shown in the example of FIGS. 1A and 1D.

The polymers comprising the proximal tubular cover 109 and the distaltubular cover 109 are heat set using heat shrink tubing or othercompression methodology and heat, such as that generated by a heated airflow source, radiant heat source, induction heater, radiofrequencyheater, or the like. Alternatively, the proximal tubular cover 109 andthe distal tubular cover 109 may be set by overcoating the catheter byextrusion, dip coating, spray coating, vapor deposition, etc.

The kink resistant member 106 includes metallic structures 206 a, 206 b,206 c (FIG. 2A) in the form of helical coil (FIG. 3B) or braid (FIG.3C). With a helical coil, the winds (i.e., helical convolutions) ofmetallic structures 206 a, 206 b, 206 c are disposed such thatdistributed flexibility can be generated along the lengths of thecatheter shaft. With a braid, the pics are disposed such thatdistributed flexibility can be generated along the lengths of thecatheter shaft. The metal used in metallic structures 206 a, 206 b, 206c can be nitinol, stainless steel, cobalt-nickel alloy, titanium, or thelike. Metallic structures 206 a, 206 b, 206 c may be formed by windingone or more wires to form a helical coil or a braid. The wires may havea flat-wire cross-section, a circular cross-section, or any otherpolygonal cross-section. Alternatively, in other embodiments, metallicstructures 206 a, 206 b, 206 c may be formed from a metallic tube thatis laser cut, chemically etched, or grinded to form a desired patternfor metallic structures 206 a, 206 b, 206 c. In another embodiment,metallic structures 206 a, 206 b, 206 c may be built upon a removablesubstrate by electrodeposition, vapor deposition, sintering, or anyother processes that may be used to build metallic structures 206 a, 206b, 206 c on a removable substrate.

The gap within the metallic winds of the helical coil or pics in thebraid are filled with polymeric kink resistant members 207 a and 207 b,which can cause the flexibility to be substantially evenly distributed,or directed along a specific axis. The polymeric kink resistant member207 may be a thermoset polymer (e.g., thermoset urethane),thermoplastic, or the like. Additionally, polymeric kink resistantmembers 207 a and 207 b may be a polymer that is firmed up by solventevaporation, cross linking, or a room-temperature vulcanized (RTV)polymer. Moreover, metallic structures 206 a, 206 b, 206 c may beovercoated by extrusion, dip coated, spray coated, vapor deposition,etc.

The kink resistant member 106 can beneficially be created such that thereinforcement becomes more flexible moving distally by changing the gapor thicknesses of metallic structures 206 a, 206 b, 206 c and/orpolymeric kink resistant members 207 a and 207 b. Additionally theflexibility can also be adjusted be changing the thicknesses andmaterials of the inner sleeve 105 and/or outer tubular covers 108 and/or109.

The proximal end of the catheter is additionally provided with luer or amanifold 110 having one or more access ports as is known in the art.Generally, the manifold is provided with a guidewire port in anover-the-wire construction, an aspiration port, and a catheter insertionport. One or more of these features can be embodied within a singleport. Alternatively, the aspiration port may be omitted if the procedureinvolves removal of the guidewire proximally from the guidewire portfollowing placement of the aspiration catheter, and aspiration throughthe guidewire port. Additional access ports may be provided as needed,depending upon the functional capabilities of the catheter. The manifoldmay be injection molded from any of a variety of medical grade plastics,or formed in accordance with other techniques known in the art.

The proximal body segment will exhibit sufficient column strength topermit axial positioning of the catheter through a patient'svasculature. The catheter body may further comprise other components,such as radiopaque fillers; colorants; reinforcing materials;reinforcement layers, such as braids and helical reinforcement elements;or the like. In particular, the proximal body segment may be reinforcedin order to enhance its column strength and torqueability while limitingits wall thickness and outside diameter.

When present, an optional radiographic marker 112 will typically beprovided at least at the distal end of the catheter 100. Otherradiopaque markers may be provided elsewhere, such as on the supportcoil, if it is not already radiopaque. One embodiment of a radiopaquemarker that may be used comprises a metal band, which is fully recessedwithin the distal end of the proximal body segment. Suitable markerbands can be produced from a variety of materials, including platinum,gold, and tungsten/rhenium alloy. The radiopaque metal band may berecessed in an annular channel formed at the distal end of the proximalbody segment.

Diameters outside of the preferred ranges may also be used, providedthat the functional consequences of the diameter are acceptable for theintended purpose of the catheter. For example, the lower limit of thediameter for any portion of tubular body in a given application will bea function of the number of fluid or other functional lumen contained inthe catheter, together with the acceptable minimum aspiration flow rateand collapse resistance.

Tubular catheter body must have sufficient structural integrity (e.g.,column strength or “pushability”) to permit the catheter to be advancedto distal locations without buckling or undesirable bending of thetubular body. The ability of the body to transmit torque may also bedesirable, such as to avoid kinking upon rotation, to assist insteering. The tubular catheter body, and particularly the distalsection, may be provided with any of a variety of torque and/or columnstrength enhancing structures. For example, axially extending stiffeningwires, spiral wrapped support layers, braid(s) or woven reinforcementfilaments may be built into or layered on all or part of the tubularcatheter body.

In many applications, the proximal section will not be required totraverse particularly low profile or tortuous arteries. For coronaryvascular applications, for example, the proximal section will be mostlyor entirely within the relatively large diameter guide catheter. Thetransition can be located on the catheter shaft to correspondapproximately with the distal end of the guide catheter when the balloonand/or distal end is/are at the treatment site. For certain otherapplications, such as intracranial catheterizations, the distal sectionis at least about 5 cm long and small enough in diameter to pass throughvessels as small as 3 mm or 2 mm or smaller. Catheters for thisapplication may have a proximal section length of between about 60 cm toabout 150 cm and a distal section length of between about 5 cm to about15 cm, and the distal section is able to track a tortuous path of atleast about 5 cm through vessels of less than about 3 mm lumen ID.

The number of catheter body sections may vary. For example, distalsection 103 may comprise a first distal section and a second distalsection. The dimensions (e.g., width, thickness) of the metal structure206 and/or the outer cover 108 may vary between the two distal sections,thereby causing them to have different properties.

Table 1 below shows examples of inner diameter to wall thickness ratiosfor catheters of the present disclosure in sizes ranging from 4 Frenchto 8 French. In some embodiments, the inside diameter (ID) to wallthickness or wall section can include ratios from about 16:1 to about24:1.

Preferred Wall Catheter Size Wall Thickness Thickness Inside Diameter(ID) 8 French 0.0045″-0.0055″ 0.005″ 0.094″-0.096″ 7 French0.004″-0.005″ 0.0045″ 0.082″-0.084″ 6 French 0.003″-0.004″ 0.0035″0.072″-0.073″ 5 French  0.003″-0.0035″ 0.00325″ 0.059″-0.060″ 4 French0.0025″-0.003″  0.00275″ 0.046″-0.047″

In an 8 French catheter, the wall thickness can range from about 0.0045to 0.0055 inches, with a preferred wall thickness of about 0.005 inchesand the inside diameter of the catheter can preferably range from about0.094 inches to about 0.096 inches.

In a 7 French catheter, the wall thickness can range from about 0.004 to0.005 inches, with a preferred wall thickness of about 0.0045 inches andthe inside diameter of the catheter can preferably range from about0.082 inches to about 0.084 inches.

In a 6 French catheter, the wall thickness can range from about 0.003 to0.004 inches, with a preferred wall thickness of about 0.0035 inches andthe inside diameter of the catheter can preferably range from about0.072 inches to about 0.073 inches.

In a 5 French catheter, the wall thickness can range from about 0.003 to0.0035 inches, with a preferred wall thickness of about 0.00325 inchesand the inside diameter of the catheter can preferably range from about0.059 inches to about 0.060 inches.

In a 4 French catheter, the wall thickness can range from about 0.0025to 0.003 inches, with a preferred wall thickness of about 0.00275 inchesand the inside diameter of the catheter can preferably range from about0.046 inches to about 0.047 inches.

FIGS. 2A-2C illustrate cross-sectional views of a catheter 100 inaccordance with an embodiment of the present disclosure. As shown inFIGS. 2A-2C, a lumen 104 is defined by inner line 105. Metallicstructure 206 a is disposed on the inner line 105 in proximal section101, metallic structure 206 b is disposed on the inner liner 105 inmedial section 102, and metallic structure 206 c is disposed on theinner liner 105 in distal section 103. Metallic structures 206 a, 206 b,and 206 c may be composed of a single wire or multiple wires. A firstpolymeric kink resistant member 207 a is disposed between the spaces inmetallic structure 206 a while a second polymeric kink resistant member207 b is disposed between the spaces in metallic structures 206 b and206 c. An adhesive 207 c is disposed over the radiographic marker 112 toform a tip. A polymeric layer 210 is also disposed over the distal endof metallic structure 206 a. The outer cover of the catheter 100includes a proximal tubular cover 209 disposed in proximal section 101.The outer cover also includes a distal outer cover 208 that is disposedover distal section 103, medial section 102 and a portion of proximalsection 101.

FIGS. 3A-3C illustrates a side view of an aspiration guide cathetersubassembly 300 comprising a hub 302 and an inner liner 304. FIG. 3Billustrates a plurality of coil windings 306, 308, 310, detailing thecatheter liner and coil subassembly arrangement. FIG. 3C illustrates aplurality of braided sections 406, 408, 410. The subassembly 300 furthercomprises a strain relief 326, an overall length 324, a working length322, a PTFE liner length 314, a distal section length 320, a medialsection length 318, and a proximal section length 316.

Referring to FIG. 3A, the inner liner 304 can comprise PTFE, PFA, FEP,or other lubricious polymer. The exterior diameter surface of the innerliner 304 can be etched to increase its roughness. Such etching can beperformed using methodology including, but not limited to, plasmadischarge treatment, mechanical abrasion, laser etching, and the like.The inner liner 304 is generally disposed over a removable mandrel ofthe appropriate diameter, said mandrel (not shown) comprising a metalliccore and an exterior lubricious coating such as PTFE, FEP, PFA,Parylene, or the like. The hub 302 can be fabricated from a variety ofpolymers selected from materials including, but not limited to,polyethylene, polypropylene, acrylonitrile butadiene styrene (ABS),polysulfone, polycarbonate, polyvinyl chloride, polystyrene, polyester,and the like. The hub 302 can also be fabricated from metals such as,but not limited to, stainless steel, titanium, cobalt nickel alloy, andthe like. The hub 302 comprises a through lumen (not shown) that canslidably accept devices up to the indicated size of the guide cathetersubassembly 300, namely about 4, 5, 6, 7, 8, and 9 French, for example.The hub 302 can comprise a strain relief in the region where it isaffixed to the tubing of the guide catheter subassembly 300 to minimizekinking and transfer forces to the guide catheter subassembly 600 undermaximum control. Attachment between the hub 302 and other components ofthe subassembly 300 can comprise ultraviolet (UV) light curing adhesivesuch as, but not limited to, Dymax™ 1128-M-VT UV curing adhesive, or thelike. The attachment between the hub 302 and the other components of thecatheter subassembly 300 can also comprise cyanoacrylate adhesive suchas, but not limited to, Loctite 4011, and the like.

Referring to FIG. 3B, the spacing on the distal coil 310 can beapproximately 0.008, with a range of about 0.006 to 0.010 inches. Thespacing on the medial coil 308 can be approximately 0.004 inches with arange of about 0.002 to 0.006 inches. The spacing on the proximal coil306 can be approximately 0.001 inches with a range of about 0.0005 to0.002 inches. The tighter the spacing of the coils 306, 308, 310 thestiffer the system and the greater the torque carrying capability of thesystem. Thus, the proximal coil 306 is stiffer than the medial coil 308,which is, in turn, stiffer than the distal coil 310. The coils 306, 308,310 can be fabricated from nitinol with superelastic or pseudoelasticproperties. The width of the individual turns in the coil can range inwidth from about 0.001 inches to about 0.010 inches and the thickness ofthe individual turns in the coil can range from about 0.0005 to about0.005 inches. The coils 306, 308, 310 may have spring characteristicsand is not malleable. The coils 306, 308, 310 can be fabricated fromnitinol, as previously stated, but it can also be fabricated frommaterials such as, but not limited to, cobalt nickel alloy, titanium,stainless steel, polyester, polyethylene naphthalate, and the like.

Referring to FIG. 3C, the pics per inch (PPI) on the distal braid 410can be approximately 20-50 PPI. The PPI on the medial braid 408 can beapproximately 50-100 PPI. The PPI on the proximal braid 406 can beapproximately 100-150 PPI. The smaller the PPI of the braids 406, 408,410 the stiffer the system and the greater the torque carryingcapability of the system. Thus, the proximal braid 406 is stiffer thanthe medial braid 408, which is, in turn, stiffer than the distal braid410. The braids 406, 408, 410 can be fabricated from nitinol withsuperelastic or pseudoelastic properties. The thickness of the braidstrands can range in width from about 0.001 inches to about 0.010 inchesand the thickness of the braid strands can range from about 0.0005 toabout 0.005 inches. The braids 406, 408, 410 may have springcharacteristics and is not malleable. The braids 406, 408, 410 can befabricated from nitinol, as previously stated, but it can also befabricated from materials such as, but not limited to, cobalt nickelalloy, titanium, stainless steel, polyester, polyethylene naphthalate,and the like.

Although, FIG. 3B describes the use of different coils in the proximal,medial, and distal sections of the guidewire and FIG. 3C describes theuse of different braids in the proximal, medial, and distal sections ofthe guidewire, in some embodiments, different combinations of coils andbraids can be used in the various sections to improve the torque andflexibility of the guidewire.

The liner and coil subassembly 300 construction for a catheter having aworking length 322 (catheter length exclusive of the hub, strain relief326 or any other attachments) of 105-cm is as follows: The overalllength 324 can be about 113-cm, the working or usable length 322 can beabout 105-cm, the liner length 314 can be about 110-cm, the proximalcoil length 316 can be about 96-cm, the medial coil length 318 can beabout 6-cm, and the distal coil length 320 can be about 8-cm.

The liner and coil subassembly 300 construction for a catheter having aworking length 322 of 115-cm is as follows: The overall length 324 canbe about 123-cm, the working or usable length 322 can be about 115-cm,the liner length 314 can be about 120-cm, the proximal coil length 316can be about 106-cm, the medial coil length 318 can be about 6-cm, andthe distal coil length 320 can be about 8-cm.

FIG. 4 illustrates a side view of an aspiration guide cathetersubassembly 500 comprising a plurality of first adhesive layers 502, 504disposed over and between the coils 306, 308, 310 or braids 406, 408,410 of the aspiration guide catheter subassembly 300.

Referring to FIG. 4, the first adhesive layer 502, disposed over theproximal regions of the subassembly 500, comprises materials such as,but not limited to, Flexobond 431™, supplied by Bacon Co., Irvine,Calif. The distal first adhesive layer 504, disposed over the distalregions of the subassembly 500, comprises materials such as, but notlimited to, Flexobond 430™, supplied by Bacon Co., Irvine, Calif. Theproximal first adhesive layer 502 can be configured to provide increasedstiffness relative to that of the distal first adhesive layer 504. Thefirst adhesive layers 502, 504 generally are applied to the subassembly500 along the entire length of the tubing 314 and the thickness of thelayers 502, 504 is approximately equal to, or slightly greater than thatof the coils 306, 308, 310 or braids 406, 408, 410.

In a subassembly 500 having a usable or working length of 105 cm, thelength 512 of the proximal first layer of adhesive 502 can be about93-cm, ranging from about 80-cm to about 100-cm. In a subassembly havinga usable length of 115 cm, the length 512 of the proximal first layer ofadhesive 502 can be about 103-cm, ranging from about 90-cm to about110-cm. The length 514 of the first distal layer of adhesive 504 canrange from about 10 to about 25-cm with a range of about 15 to about10-cm and a more preferred value of about 17-cm.

FIG. 5 illustrates a side view of an aspiration guide cathetersubassembly 600 that comprises a plurality of second layers of adhesiveproximal 602, intermediate 604, and distal 606, a proximal outer layerof polymeric coating 608, and a distal layer of outer polymeric coating624. The subassembly 600 further comprises at least one radiopaquemarker band 610 and a transition ring of UV adhesive 618. The proximalsecond layer of adhesive 602 has a length 612 while the distal secondlayer of adhesive 606 has a length 616 and the intermediate second layerof adhesive 604 has a length 614. The catheter subassembly 600 furthercomprises an overlap region 620 disposed at the transition between theproximal second layer of adhesive and the intermediate second layer ofadhesive 604. The subassembly 600 further comprises an outer layer ofpolymeric shrink wrap tubing 622 in the intermediate region.

Referring to FIG. 5, the distal second layer of adhesive 606 is disposedover the distal part of the catheter subassembly 600 as well as beingdisposed over the intermediate second layer of adhesive 604.

The proximal second layer of adhesive can have a length of about 91-cm(range about 80-cm to about 100-cm) for a catheter having a 105-cmworking length and about 101-cm (range about 90-cm to about 110-cm) fora catheter having a 115-cm working length. The length of theintermediate second layer of elastomeric adhesive can be about 5.5-cmwith a range of about 3-cm to about 7-cm. The length of the distal layerof elastomeric adhesive can range between about 15-cm and 25-cm with anexemplary value of about 19.5-cm for catheters having working lengths ofabout 105-cm to about 115-cm. The overlap region 620 can have a lengthof about 0.5-cm with a range of about 0.1-cm to about 1.0-cm. The lengthof the UV curable adhesive ring 618 can range from about 0.5-mm to about2-mm with an exemplary value of about 1.0-mm.

In an embodiment, the radiopaque marker band 610 can be fabricated fromplatinum iridium wire having a diameter of about 0.002 inches. Materialscomprised by the radiopaque marker 610 can include platinum,platinum-iridium, gold, tantalum, barium sulfate, bismuth sulfate, andthe like. The radiopaque marker 610 can comprise or be configured as acoil of round wire or flat wire, or it can be configured as an axiallyelongate cylindrical band, as a serpentine band of wire, or the like.The radiopaque marker 610 can comprise a length of about 0.5 mm to about5-mm. The radiopaque marker 610 can be embedded within the elastomericadhesives and be disposed between the innermost layer 304 and theoutermost layer of polymer 608 and 624.

The outermost layers of polymer 608, 622, and 624 can be fabricated frommaterials such as, but not limited to, polyester (PET), polyimide,Pebax™, polyamide, or the like. In some embodiments, the outermostlayers of polymer 608 in the proximal region can be configured as heatshrink tubing having a thickness of about 0.001 inches. The outermostlayer of polymer 624 in the distal region can comprise polyimide(Pebax™) heat shrink tubing having a thickness of between about 0.0005and 0.002 inches. The distal outer second polymer layer can be sourcedfrom Iridium corporation. The intermediate outer layer of polymer 622can comprise polyester (PET) having a wall thickness of about 0.00025inches, with a range of about 0.0001 to about 0.001 inches.

The second layer of adhesive in the proximal region 602 may compriseFlexobond 431 but can also comprise other similar materials, such as butnot limited to other 2-part urethane adhesives, 1-part urethaneadhesive, or the like. The second layer of adhesive in the intermediateregion 604 comprises Flexobond 430 but can also comprise other similarmaterials, such as but not limited to other 2-part urethane adhesives,1-part urethane adhesive, or the like. The second layer of adhesive inthe distal region 606 may comprise Flexobond 430 soft mix but othersimilar materials can also be used.

FIG. 6 illustrates a side view of an aspiration guide cathetersubassembly 700. In catheter subassembly 700 an additional coating layer702 may be applied to the distal end of catheter. Coating layer 702 mayinclude coating base, a crosslinker A coating, and/or crosslinker Bcoating.

FIG. 7 illustrates a guide catheter 800 according to another embodimentof the present disclosure. In this example, guide catheter 800 issimilar to guide catheter 100 described above. Whereas guide catheter100 has a straight configuration, guide catheter 800 has a modified Jshape configuration.

In some embodiments of the disclosure, an optional balloon, such as acompliant balloon formed of material such as latex, silicone,polyurethane, C-Flex™ thermoplastic elastomer, Chronoprene™, Santoprene™or the like, may be positioned at or near the distal end of the elongatecatheter body. Such optional balloon may be useful for occluding flowthrough the blood vessel in which the catheter is positioned when suchflow occlusion is desired.

In at least some embodiments, the proximal section 101 will retainradial strength but provide lateral flexibility. Additionally, thatsection desirably has a lateral flexibility (stiffness), such as wouldbe measured by, for example, a Tinius-Olsen™ Stiffness Tester, of atleast 1,200 degrees of deflection/inch-pound (measured at 20 degrees to30 degrees of deflection, with a 0.005 lb load, over a 0.25″ span),preferably 2,500 degrees of deflection/inch-pound. The radialcompression strength of the section is quite high as compared to otherdistal sections found on comparable catheter distal sections of priorart guide catheters.

Access for the catheter of the present disclosure can be achieved usingconventional techniques through an incision on a peripheral artery, suchas right femoral artery, left femoral artery, right radial artery, leftradial artery, right brachial artery, left brachial artery, rightaxillary artery, left axillary artery, right subclavian artery, or leftsubclavian artery. An incision can also be made on right carotid arteryor left carotid artery in emergency situations.

The construction disclosed herein is suitable for guide catheter as astand-alone device. This construction results in a highly flexibledevice having high column strength, torqueability, superiorkink-resistance unachievable in prior art devices having a thin walltube of this size, and high tensile strength.

It is to be appreciated that the disclosure has been described hereabovewith reference to certain examples or embodiments of the disclosure butthat various additions, deletions, alterations and modifications may bemade to those examples and embodiments without departing from theintended spirit and scope of the disclosure. For example, any element orattribute of one embodiment or example may be incorporated into or usedwith another embodiment or example, unless otherwise specified of if todo so would render the embodiment or example unsuitable for its intendeduse. Also, where the steps of a method or process have been described orlisted in a particular order, the order of such steps may be changedunless otherwise specified or unless doing so would render the method orprocess unworkable for its intended purpose. All reasonable additions,deletions, modifications and alterations are to be consideredequivalents of the described examples and embodiments and are to beincluded within the scope of the following claims.

1-20. (canceled) 21: A catheter comprising: a catheter body comprising:an inner liner defining an inner lumen; a kink resistant membercomprising a metallic member defining a plurality of gaps and apolymeric material disposed within the gaps; and an outer cover, whereinthe kink resistant member is positioned between the inner liner and theouter cover, the polymeric material being different from the materialsof the inner liner and the outer cover, the outer cover comprising: aproximal outer cover; and a distal outer cover distal to the proximalouter cover and positioned over at least part of the proximal outercover; wherein a distal region of the catheter body has an innerdiameter to wall thickness ratio greater than or equal to 16:1. 22: Thecatheter of claim 21, further comprising a polymeric layer disposedbetween the metallic member and the distal outer cover. 23: The catheterof claim 22, wherein the polymeric layer is positioned over a distal endof the metallic member. 24: The catheter of claim 21, wherein thepolymeric material disposed within the gaps comprises a proximalpolymeric material portion and a distal polymeric material portion, thedistal polymeric material portion being positioned between the proximalpolymeric material portion and a distal end of the catheter body, theproximal polymeric material portion being stiffer than the distalpolymeric material portion. 25: The catheter of claim 24, wherein athickness of each of the proximal polymeric material portion and thedistal polymeric material portion is greater than or equal to athickness of the metallic member. 26: The catheter of claim 24, whereinthe proximal polymeric material portion and the distal polymericmaterial portion each comprise an adhesive. 27: The catheter of claim26, wherein the proximal polymeric material portion comprises a firstproximal layer of adhesive and the distal polymeric material portioncomprises a first distal layer of adhesive, the catheter body furthercomprising: a second proximal layer of adhesive; an intermediate layerof adhesive; and a second distal layer of adhesive, the intermediatelayer of adhesive being positioned between the second proximal layer ofadhesive and the second distal layer of adhesive. 28: The catheter ofclaim 27, wherein the second distal layer of adhesive is disposed overthe intermediate layer of adhesive. 29: The catheter of claim 27,further comprising a ring of ultraviolet (UV) adhesive between thesecond proximal layer of adhesive and the intermediate layer ofadhesive. 30: The catheter of claim 21, further comprising a hydrophiliccoating on an outer surface of the outer cover. 31: The catheter ofclaim 21, further comprising a balloon positioned at or near a distalend of the catheter body. 32: The catheter of claim 21, wherein themetallic member comprises a coil. 33: The catheter of claim 32, whereinthe coil defines a helix defining a helical gap, a width of the helicalgap increasing in a distal direction. 34: The catheter of claim 32,wherein the coil defines a helix defining a helical gap having acontinuous a width along a length of the coil. 35: The catheter of claim21, wherein the metallic member comprises a braid. 36: The catheter ofclaim 21, wherein the polymeric material comprises a thermoset polymer.37: The catheter of claim 21, wherein the distal region has a lateralflexibility of greater than 1200 degrees of deflection per inch-poundforce. 38: The catheter of claim 21, wherein the distal region has akink radius of about 0.174 inch+/−0.008 inch or less. 39: The catheterof claim 21, further comprising a radiographic marker distal to themetallic member. 40: The catheter of claim 39, further comprising anadhesive between the radiographic marker and the outer cover. 41: Acatheter comprising: a catheter body comprising: an inner liner definingan inner lumen; a coil defining a plurality of gaps; a polymericmaterial disposed within the gaps, wherein the polymeric materialcomprises a proximal polymeric material portion and a distal polymericmaterial portion, the distal polymeric material portion being positionedbetween the proximal polymeric material portion and a distal end of thecatheter body, wherein the proximal polymeric material portion isstiffer than the distal polymeric material portion; and an outer coverpositioned radially outward of the inner liner, wherein the coil and thepolymeric material are positioned between the inner liner and the outercover, the polymeric material being different from the materials of theinner liner and the outer cover, and wherein the outer cover comprises:a proximal outer cover; and a distal outer cover distal to the proximalouter cover and positioned over at least part of the proximal outercover. 42: The catheter of claim 41, wherein a distal region of thecatheter body has an inner diameter to wall thickness ratio greater thanor equal to 16:1. 43: The catheter of claim 41, further comprising apolymeric layer disposed between the metallic member and the distalouter cover, wherein the polymeric layer is positioned over a distal endof the coil. 44: A method comprising: forming a catheter body, whereinforming the catheter body comprises: positioning a metallic member overan inner liner, the inner liner defining an inner lumen; disposingpolymeric material within gaps of the metallic member; and disposing anouter cover over the metallic member and the polymeric material, whereinthe polymeric material is different from the materials of the innerliner and the outer covering, wherein disposing the outer cover over themetallic member and the polymeric material comprises: positioning aproximal outer cover over the metallic member and the polymericmaterial; and positioning a distal outer cover over the metallic memberand the polymeric material distal to the proximal outer cover and overat least part of the proximal outer cover, wherein a distal region ofthe catheter body has an inner diameter to wall thickness ratio greaterthan or equal to 16:1. 45: The method of claim 44, further comprisingpositioning a polymeric layer over the metallic member prior topositioning the distal outer cover over the metallic member.